Electrical transmission through cables generates heat which reduces the efficiency of the electrical transmission, particularly over relatively long distances. This is especially the case when the electrical transmission cable is a superconducting cable.
Superconductivity is the phenomenon wherein certain metals, alloys and compounds, such as YBCO, REBCO and BSCCO, at very low temperatures lose electrical resistance so that they have infinite electrical conductivity. It is important in the use of superconducting cable to transmit electricity, that the cooling, i.e. refrigeration, provided to the superconducting cable not fall below a certain level lest the cable lose its ability to superconduct and the electrical transmission be compromised. While systems which can provide the requisite refrigeration to superconducting cable are known, such systems are costly, complicated and subject to breakdown. Moreover, known systems typically manifest an inefficient use of the coolant.